keyword moderation is terrible and only affects the language(s) you know about. It doesn't actually prevent the content (the goal of these types of filters) from being served. It'd be like a virus scanner preventing a program from running because it had the name 'virus' in it ... which would prevent itself from running -- probably.
My favorite is the online name censoring in video games. Dark Souls infamously just does a straight check of any string match within the name against a big list of no-no words. So in this fantasy game where everyone is running around as a knight, anyone who has "knight" in their game will appear as "k***ht" to other players.
There's also a famous image I've seen online from another game where the guy's name was Nasser which appeared for everyone else in-game as "N***er"
I remember a conversation with some using an in-house file transfer system “Oh you won’t be able to send more than X GBytes, at that point the chances that the base64 encoding contains a banned rude word become too high, and the transfer will fail”
Maybe it's time to convert base64 to high UTF8-areas. I guess there won't be any keyword-filter yet for ancient egyptian hieroglyphs. I'm curious whether there are already emoji-filters...